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I currently use Varathane 900 for a finish. Looks good easy to use. I was contemplating on using a spar finish. Any recommendations? I am not interested in hunting through old hardware store looking for it. Something currently being produced that can be recommended with the % of thinning would be appreciated.  (Adam Vigil)

In my mind there is no better spar than Pratt & Lambert #61 Spar Varnish. I thin 10 - 15%.  (Marty DeSapio)

I have been under the impression that if a varnish or a urethane has “Spar” in its title then it has Tung oil in the formulation.  A lot of the varnish companies now only list the main ingredient as Phenolic oils so as not to give away formulation secrets.  So it is harder to find out the exact composition of these varnishes.  Specifically, I wanted to try out the Pratt & Lambert #61 Spar varnish, and if anyone has tried it, I would love to hear their opinions.  (Robert Cristant)

Funny, I thought spar meant that it was an exterior varnish with UV inhibitors in it.  (Larry Puckett)

Is there a difference between Spar and Yacht varnish?

They sell yacht varnish here in Ireland but not Spar.  As far as I can see it has all the good stuff we look for in Spar varnishes (non-polymer tung oil or whatever it is)  (Nick Kingston)

It's probably the same stuff.

Spar varnish can be interior as well as exterior. The difference is in the UV inhibitors in the mix.  As I have always understood it the thing that differentiates spar varnish from other varnishes is mainly that you can sand it back and recoat it while with most varnishes you have to remove it all to bare wood or the varnish wont hold. (Tony Young)

Spar varnish is a term that applies to an exterior varnish that is suitable for finishing the spars on a boat (masts, booms etc) and other woodwork that is troublesome to maintain because of the severe reflected sunlight and expansion and contraction and moisture and other weather that boats are exposed to.  Spar varnish did not include UV inhibitors until comparatively recently in its history and you can buy Spar without UV inhibitors still today.

The ability to sand and coat spar varnish, as opposed to a non-spar varnish really has nothing to do with the name spar.  It has to do with the plastic, or Bakelite, or other types of resins in the varnish.  Polys are harder to recoat because subsequent coats do not melt into undercoats as do some non poly varnishes.  Poly's have a specific window of opportunity for easy recoating where more traditional varnishes may be recoated most anytime because they never really dry hard.  We always go to the bare wood every other year on the boats in our family and we use Interlux Schooner or Spitani (I hope I have spelled that right).

All this being said, I don't think too many folks would really be happy using an old-fashioned varnish because they never really set up hard enough to move around wraps or polish out.  Old fashioned Copal varnish gets hard, but it gets brittle, too.  (Chris Lucker)

The term Spar is generally used to designate a varnish having a phenolic resin as its base ingredient. The oil used is irrespective of the use of the term Spar. There are Spar Urethane varnishes which use a combination of resins.  (Martin-Darrell)

I have tried both Man-O-War and P&L #61 when brush varnishing rods years ago. In my opinion there is no comparison between the two. P&L #61 hands down. It just seemed to end up with a nicer finish. The stuff from the can is to thick for dipping and needs to be thinned 15-20 percent . I never dipped with MOW but have been very satisfied with P&L #61.

I always thought that the word "spar" meant it could be use exterior.  (Marty DeSapio)

Try thinning varnish with Penetrol -- just a few drops will do it when you are brushing as in your example.  Penetrol is an agent you sometimes need to add to oil paint or oil-based varnish when the weather makes the brush drag.  It is magic -- far superior to turpentine when brushing.  (Chris Lucker)

I use the P&L 61 and really like it.  It takes about two days between coats before you can sand without balling, you can get away with a 24 hours between coats but I add an extra day just to be safe.  It has more of an amber tint to it than other varnishes, like MoW, but I like the way it makes the cane look a little darker.  (Kyle Druey)

Also check WoodfinishingSupplies.com Varnish FAQ.  The web site in itself is interesting.  (Reed Curry)  (The 2 links that Reed supplied are no longer valid.)

Thanks for sharing those sites.  Parts of the site I found while browsing around were fascinating.  A lengthy portion of the faq site is quoted below:

Many woodworking operations in the shop will cause the surface of the wood to be burnished, i.e. the fibers closest to the surface will be crushed and even hand-planing or scraping a surface will cause this effect. So it is essential that you use sandpaper to produce an surface condition conducive to the finishing process. There are several types of sandpaper available for use in finishing, but for surface prep I have had the best luck using garnet paper or a combination of stearated aluminum oxide/stearated silicon carbide paper for the rough grits and garnet for the final sanding. Wherever you start in the range of grits available, you must not skip grits along the way. For example, if you start with 100 grit paper, you should then use 120 grit paper, followed by 150 grit, and so on. Whether you hand sand or power sand, you must be consistent for best results. In either case let the sandpaper do the work! Where you end-up in the grit range is a matter of several complex considerations if you want to think about it too hard. However, a general rule of thumb when using garnet paper for the final sanding is to stop at 180 grit for hard-textured woods such as oak or cherry and 220 grit for soft-textured woods such as pine or mahogany. In any case, you don't want the surface to possess any sheen at all, this would indicate a bit of burnishing, so it should be quite dull in appearance. The exceptions to this rule of thumb are usually driven by the type of wood and the coloration processes involved, both of which may require a final sanding with a finer grit paper.

Obviously this isn't what most of us do with bamboo.  We use the finest paper possible.  I know bamboo isn't wood, but I doubt that explains the reasons we seek to finish so differently than wood.  (Harry Boyd)

That's very interesting about the sand paper. I know several fine cabinet makers and one instrument maker reasonably well who wont allow sand paper to even be in the workshop. It scours the surface of the finished hardwood. It's finish with a plane or scraper only for them as the "burnished" finish has the best luster while the grain of wood when sanded is almost smeared.  I remember visiting one cabinet maker who lived in Brisbane and sold Japanese saws as a side line and was in the middle of a cabinet he creating the secrete panel all good cabinets should have for the house the Governor General of Australia in Canberra lives in. That's more significant than making a bamboo rod for the president because this thing will assuming the country survives that long will still be there for 500-600 years.  I made the fatal error of asking about sand paper and he almost lost his dentures as he spat and spluttered about what a fecking mess it made of perfectly good work.  He was very serious about this. I think he was making sure I understood he never used it just in case I ever mentioned sandpaper and his name in the same sentence which I am told can be long.

ALSO, if you ever read any of Krenov who some hold as a demigod of cabinet work and others dismiss as being a self centered wanker also holds that files and sand paper have no place in a cabinet makers workshop.  Just thought you may be interested.  (Tony Young)

I agree with Tony and James Krenov.  Sandpaper is for the power tool crowd.

The best surface is fresh from a razor sharp plane blade.  Get hold of James Krenov's "The Fine Art of Cabinet Making".  He's just as particular as this group is in the quality of his work.  Read him 20+ years ago and changed the way I looked at wood.  Still use wooden planes too - Japanese and JK style.

If you must use sandpaper, Harry's comments about not skipping grades and letting the paper do the work are right on.   (Kurt Clement)

My first rod is ready for finish, grips, and wraps. I'm clueless on wrapping so I'm going to Alex Wulff's house next week for help.  Before then I want to complete my grip and think about finish.

Method of finish.  I plan on using Spar Urethane to finish the rod.  Does anyone out there wipe on finish instead of dipping or dripping?  I have achieved great results on other woodworking projects using a homemade wiping varnish (blend of urethane, mineral spirits, and a little oil).  I know I will needs more coats this way but I'm not set up to dip or drip at this time.  (Aaron Gaffney)

If you like the wipe on method you use for other woodworking, I'd use it on the rod too.  (Neil Savage)

I brush and wipe on my final finishes. I also polish with rottenstone and Finesse-it II after the last finish coat to provide a final varnish surface.  (Frank Paul)

What is rottenstone?  I've seen it mentioned several times, but I am clueless as to what it is.  (Aaron Gaffney)

It's a polishing abrasive, a bit finer than pumice.  I think it's ground up limestone.  You mix it with either oil or water and rub out your finish.  (Neil Savage)

I just found a new Bullseye Spar Varnish at my local Lowes. It is made by Zinsser and comes in gloss, semi-gloss, and satin finishes and they say it si a new product. The MSDS indicates it contains about 50% mineral spirits, 5 % low odor spirits, 5% UV absorber. The resin is alkyd and long oil alkyd. The satin and semi-gloss version contains some additional garbage but the main thing is some SiO2 (silicon dioxide) to cut the gloss. I just got the info sheets from the company by email so guess I’ll go back and buy some tomorrow to test. Right now it’s the lone alkyd spar I can get locally. (Larry Puckett)

Well, a few weeks ago I couldn’t find a can of spar varnish within 100 miles now I an over run with it. First I finally find a Ace store that stocks theirs. Then I go by Lowes and they have a new spar varnish from Zinsser/Bullseye. So today I go back to buy a can and darned if they don’t also have spar varnish made by Cabot (owned by Valspar) in quarts and gallons! So my question is has anyone out there had any experience with the Cabot spar? They’re all an alkyd resin based spar so I figure they must all be pretty much the same stuff but I’d like that cozy feeling of knowing someone else had tried them first.  (Larry Puckett)

I used a quart a few years ago. I thought it was pretty good  but I couldn't find anymore. Nothing special, much like Helmsman.  (Doug Easton)

Upon talking to the buyer at Lowe's, they've stopped stocking Helmsman's Spar Urethane and moved to Cabot's Spar Varnish. The reasoning was that they couldn't stock the Helmsman in CA (and a few other states) because of the environmental restrictions on content. I can only assume that the rest of the states had stores restocked to avoid carrying dual inventories. I've been assured it will perform at least as well, and the "reformulated" Helmsman was not the ideal replacement for its predecessor.  (Mike St. Clair)

IMHO, most of the "reformulated" finishes aren't as good as their predecessors.  Guess we'll have to get used to it though.  SIGH...  (Neil Savage)

Well, the great thing is they have both polyurethane and alkyd spar varnish now. If it is anywhere near as good as MOW then I'm a happy boy.  (Larry Puckett)

I just refilled my dip tube with Helmsman Spar, it's still available in NJ, and found it VERY different from the batch I bought 3 years ago.  The old varnish I thinned about 10% and adjusted my draw rate to around 4 inches per minute to get sag-free coatings.  The new stuff I DID NOT thin and had to adjust my draw rate to about 1.8 inches per minute to prevent sags!!  The new stuff has a much lower viscosity.  (Al Baldauski)

I found the same thing, it is not the same and does not seem to finish out with that "snap."  (Tony Spezio)

Yep, I brought this up right after they changed formulas. The old stuff had a little bit of an amber hue and was thicker. And while it's sill OK, it definitely isn't as good as the old formula. It goes without saying, when the words new and improved appear on a product, you can bet your A double scribble that while it may be new, it sure ain't improved.  (Will Price)

I don't understand why a finish with a lower viscosity would require a slower extraction speed to prevent sags.  (Henry Mitchell)

I am going to insert what I have recently learned on the topic. I decreased my draw rate AND warmed my tube/liquid. Fixed my runs and made my finish nice and thin. VERY thin indeed. Makes multiple layers easy with little buildup. My dip tube is in a simple wooden case with a l00 watt light bulb on a rheostat (timer) so I can adjust the liquid to 100 degrees F. My draw is via a BBQ rotisserie from the box stores that turns a 1/2" dowel at 2 RPM. Takes 10 minutes to dip a 30" section. I now just love the setup. Adjustment is all via the temp in the tube with the dimmer switch.  Hope  this helps you or a lurker ;-)  (Barry Janzen)

The faster you draw from  a liquid the thicker the wet film.  The thicker the wet film the greater tendency to run.  The lower the viscosity the greater the tendency to run.  This is all modified by the rate at which the solvents evaporate from the film.  As the solvent evaporates the viscosity of the wet film increases.  So dip coating is a balancing act of all these variables.  And don’t forget temperature, too.

A slower draw rate gives a thinner wet film and allows more time for solvent to evaporate.  (Al Baldauski)

I guess I missed your initial question, and Al's answer is very correct.

But if I may elaborate (by now it's too late to stop me)

There are two major forces at work here. Surface tension and gravity + the factors that Al mentioned, viscosity/temperature. The viscosity will vary with the temperature, so it's nice to have a consistent temp when you dip, drain, unless someone has found a 10w-30 brand.

As you withdraw the rod the surface tension of the liquid in the tube tries to wick away the varnish from the rod. So the slower you draw the more chance it has to pull it away, leaving a thinner coat. Once the rod has cleared this boundary layer, gravity takes over and ties to make the varnish run down the rod. In both cases the viscosity will determine the outcome. The greater the viscosity (thicker) the more varnish it will leave at a given withdrawal rate, but at some point gravity will make it run (but the greater viscosity will try to resist).  The thinner the varnish the easier it will run, but more will be wicked away, so  you have a balance point for either. If you go slow enough neither will be a problem.

My findings:

What Jerry said!

I was thinking about building a CNC dip tube so I could program in the  taper and guide spacings.  This way the draw rate would be compensated for the ever-changing diameter and it would automatically pause for a preset time at the guides.  (Al Baldauski)

Yep, CNC dip tubes are fun and easy (cheaper), compared to a mill.

Yes, it's the volumetric displacement that gets you if you want to stop at all the guides. But I found that after you get the draw rate tuned, the only stop points necessary are at the cork windings and the stripping guide. I also haven't had any problem with a constant draw rate. But it sounds like fun to mess with. It was easier to just manually stop it the first time and put those DRO numbers in the code. and then run it on auto for all subsequent passes. And if you really want to get fussy you could also compensate for the varnish removed. Yuk. If you can keep the varnish temp constant most of the other problems go away. PID controller/probe attached to SSR and a thrift store electric blanket coil with controller.

And of course most of the rods I make for testing purposes I put the stripping guide in the same place, based on my arm length. And generally there isn't enough difference in surface area/volume to make much of a difference. And I do try to get cork check wraps the same length. Electronic wrap counters help there.  (Jerry Foster)

And I thought I was hot stuff with my little 35 mm film canister as a viscosity cup! Well! (Joe Arguello)

Well my response to a CNC dipper was mostly tongue-in-cheek but I do admit to having thought about it.

BTW:  The drop of level during extraction is easy enough to calculate depending on the sophistication of your controller software.  I've done it on an industrial dip coater.  (Al Baldauski)

OMG, now I have to look at a CNC dip tube? You know they were trying to warn us with that song way back "In the year 2525" do any of you remember that? Pretty soon all I'm gonna have to do is push a button and wait for the rod to come out! And I don't drink beer so what am I gonna do? Really though I taught a machinist to build rods, this guy was an old tool and die maker, short story if you looked at the tools he made they looked like they were made to NASA specs. He told me "I enjoy making the tools more than making rods" different strokes for different folks. What a country!  (Joe Arguello)

Isn't it just wonderful.

Fishing is really an amazing activity - just like getting lost on purpose, there is no telling where you might end up. There is also no end to the toyls!  (Larry Blan)

And when they get to the point of pushbutton rods, My "truth" will be vindicated. The rod is the taper.  (Jerry Foster)

Nah, gotta go with the mojo, Black magic, voodoo stuff :>)

I wish I could find an article named "The black gnat" was about a guy who sold his soul for a black gnat that was sure to work under any condition. I remember the story said he had a 'Garrison worth more than his truck' As those stories go he ended up doomed to having to sell the gnat to someone else in order to get out from under it.  (Joe Arguello)

I don' know Jerry.  With all the talk of CNCing everything my thoughts keep coming back to an old Woody Allen movie; Sleeper!

I mean it's amazing and all that but I don't really NEED to be Amazed any more.  Of course some of this may be because I'm  able to retire now after spending the last 12-13 years behind a computer 9-10 hours a day.  Except for internet and email I'm sick of computers. I built myself a roughing mill that gives me a jump on getting the strips roughed out to the correct angle and a lot of the excess bamboo out of the way.

Once ya got the strip roughed and heat treated it doesn't take long to get the strips planed down to final.  It also gives me a feeling that I'VE  done something. Of course my tapers are only slightly (if at all) modified classic tapers.  But then, as has been often stated, "How many tapers can there be?"

Now if ya'd come up with a CNC rod wrapper I just might be interested! :>)  (Larry Swearingen)

I built the CNC dip tube to save wasting time watching the stupid thing draw so I could waste time doing something else. As a matter of fact, I'm dipping a rod right now, or it's dipping itself, depending on how you want to view it. It gives all you craftsman another brochure-ware edge, you can now claim that your rods are manually dipped (sorta like hand planed).  (Jerry Foster)

Actually I was sitting here pondering how to make an 'automatic' dip tube using gears. pulleys, cams and stuff. Has to look like it came right of a Jules Vern's novel, now that would give you some brochure-ware! On that note I built a mill that uses a tapered form you know kinda retro. But like Charlie Jenkins once told me "you can spend a whole lot of time tuning these things up" it now sits under my work bench collecting  dust, kinda works, but someday.........

But not to despair just like my 35 mm viscosity cup, I made a fixture so I could dip both tips at once :>) Hey you gotta start somewhere and I'm all about saving time, too waste on something else, perhaps a  nap or something.  (Joe Arguello)